vmap allocation for size 8192 failed ---- 原因及解决方法(求解)

在boot ARM Linux kernel时，解压完kernel后，就不能继续运行。log信息如下：

-------------------------------------------------------------------------------------------------------------------------------------------------

Starting kernel ...
Uncompressing Linux............................................................................................................................................................................................. done, booting the kernel.

-------------------------------------------------------------------------------------------------------------------------------------------------

不知道为什么会出现这种情况。于是打开kernel的low level debug信息。具体参见：http://blog.csdn.net/voice_shen/article/details/6947737

其log信息如下：

-------------------------------------------------------------------------------------------------------------------------------------------------

Mount-cache hash table entries: 512
<6>CPU: Testing write buffer coherency: <4>vmap allocation for size 8192 failed: use vmalloc=<size> to increase size.
<4>vmap allocation for size 8192 failed: use vmalloc=<size> to increase size.
failed, unable to map memory

<1>Unable to handle kernel paging request at virtual address bffcc000
<1>pgd = 80004000
<1>[bffcc000] *pgd=00000000
Internal error: Oops: 805 [#1]
<d>Modules linked in:
CPU: 0 Not tainted (2.6.31.8 #30)
PC is at memcpy+0x6c/0x3a4
LR is at 0x0
pc : [<80034dcc>] lr : [<00000000>] psr: 20000013
sp : a002de3c ip : 00000017 fp : a002deac
r10: 00804111 r9 : 00000000 r8 : 00000000
r7 : 805a9798 r6 : a001ec60 r5 : 00000000 r4 : 00000000
r3 : 00000000 r2 : 000001d0 r1 : a002c020 r0 : bffcc000
Flags: nzCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel
Control: 0005397f Table: 00004000 DAC: 00000017
Process khelper (pid: 6, stack limit = 0xa002c270)
Stack: (0xa002de3c to 0xa002e000)
de20: bffcc000
de40: a001ec60 00000000 a001e960 bffcc000 00000000 801a9a28 8064c9b7 0074f581
de60: 00000000 a002df08 00000000 00000000 a2281805 00000000 1007882d 2446942f
de80: 88050420 00004011 00000000 00804111 00000000 00000000 00000000 00000000
dea0: a002defc a002deb0 801aa7b0 801a9950 00000000 00000000 00000000 805a9320
dec0: 00000000 a0017c70 00000001 00000003 a002df04 00004011 00000000 a002df08
dee0: a001fe60 801ba0f4 00000000 00000000 a002df74 a002df00 80158ef0 801aa654
df00: 00000000 00000000 00000000 a001fe60 801ba0f4 801adec0 00000000 00000000
df20: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
df40: 00000000 80032640 00000013 00000000 a001edec a001fe60 00000000 a0001900
df60: a002c000 00000000 a002df8c a002df78 801ba0b8 80158e90 801ba064 a0001908
df80: a002dfc4 a002df90 801bad18 801ba074 8004046c 00000000 a001ec60 801be680
dfa0: a002dfa0 a002dfa0 a002dfcc a0023f28 a0001900 801babf8 a002dff4 a002dfc8
dfc0: 801be240 801bac08 00000000 00000000 a002dfd0 a002dfd0 00000000 00000000
dfe0: 00000000 00000000 00000000 a002dff8 801adec0 801be1c8 92a32535 c60829c6
Backtrace:
[<801a9940>] (copy_process+0x0/0xd04) from [<801aa7b0>] (do_fork+0x16c/0x2d8)
[<801aa644>] (do_fork+0x0/0x2d8) from [<80158ef0>] (kernel_thread+0x70/0x80)
[<80158e80>] (kernel_thread+0x0/0x80) from [<801ba0b8>] (__call_usermodehelper+0x54/0x90)
r8:00000000 r7:a002c000 r6:a0001900 r5:00000000 r4:a001fe60
[<801ba064>] (__call_usermodehelper+0x0/0x90) from [<801bad18>] (worker_thread+0x120/0x1ac)
r5:a0001908 r4:801ba064
[<801babf8>] (worker_thread+0x0/0x1ac) from [<801be240>] (kthread+0x88/0x90)
r7:801babf8 r6:a0001900 r5:a0023f28 r4:a002dfcc
[<801be1b8>] (kthread+0x0/0x90) from [<801adec0>] (do_exit+0x0/0x5b4)
r7:00000000 r6:00000000 r5:00000000 r4:00000000
Code: f5d1f05c f5d1f07c e8b151f8 e2522020 (e8a051f8)
<4>---[ end trace 1b75b31a2719ed1c ]---

-------------------------------------------------------------------------------------------------------------------------------------------